Process for making laminated film article having inflatable chambers

ABSTRACT

An inflatable laminated article is prepared by contacting a first film ( 8 ) with a second film ( 10 ), and heating selected portions of at least one the first and second films to a temperature above a fusion temperature of the first and second films, so that the first and second films are heat sealed to one another. The heat sealing is carried out in a pattern which provides a plurality of inflatable chambers between the first film and the second film. The first and second films are for warded at a speed of at least “0.6096 m/s” (120 feet per minute) while coming into contact with one another. The heating is carried out by contacting the first film with a heated raised surface roller ( 16 ) having a release coating thereon.

FIELD OF THE INVENTION

The present invention relates generally to methods of making laminatedfilm articles, apparatus for making laminated film articles, and moreparticularly, to apparatus and methods for making laminated filmarticles having inflatable chambers and channels.

BACKGROUND OF TB INVENTION

Conventional cushion materials include thermoformed sealed laminatearticles such as Bubble Wrap® cushioning material. However, it is alsoknown to prepare laminated inflatable articles which can be shipped to apacker uninflated, and inflated immediately before use. Such inflatablearticles are typically made from two heat sealable films which are fusedtogether in discrete areas to form one or more inflatable chambers.

Conventional methods of making cushion material, such as Bubble Wrap®cushioning material, use a vacuum source to deform polymer film to formbubbles or pockets that can be filled with air (or other gases) to formbubbles. Such products can be made using a heated drum having recessesthat are connected to a vacuum source. When vacuum is applied, each ofvarious regions of the heated film in contact with the drum is drawninto a recess on the drum. The heated film is deformed and thinned inthe regions drawn into the recess by the vacuum process. One side of theresulting film remains “flat”, while the other side is not flat, butrather is “thermoformed”. A second film, which preferably is a flatfilm, i.e., not thermoformed, is fused to the “flat side” of the formedfilm, resulting in a plurality of sealed, air-filled “bubbles.”

SUMMARY OF THE INTENTION

The present invention provides a method of making an inflatable articleat relatively high speed, by bringing a first film into contact with asecond film and heating selected portions of at least one the first andsecond films to a temperature above a fusion temperature of the firstand second films, so that the first and second films are heat sealed toone another to produce a laminated article. The sealing forms a heatseal pattern which provides a plurality of inflatable chambers betweenthe first film and the second film. The first and second films areforwarded at a speed of at least 120 feet per minute while coming intocontact with one another. The heating is carried out by contacting thefirst film with a heated raised surface roller having a release coatingthereon. At least the seal layers of one or both of the films are heatedto a temperature at or above a temperature at which the one or more ofthe seal layers will fuse. Preferably, the raised surface roller rotatesat a speed which matches the speed at which the first and second filmsare being forwarded. Preferably, the raised surface roller has a surfaceroughness of from 50 to 500 rms. Preferably, the first and second filmsare heat sealed to one another under a combination of heat and pressure.

Preferably, the pressure is produced by means for forming a nip area.The means for forming a nip area includes not only nip rolls, but alsogas and fluid impingement, film tensioning against the raised surfaceroller, and electrostatic nip, as disclosed in U.S. Pat. No. 5,116,444,to John G. Fox, which is hereby incorporated, in its entirety, byreference thereto. Preferably, the means for forming a nip area is acontact roller in a nip relationship with the raised surface roller.

Preferably, the first film is brought into contact with the raisedsurface roller and heated to the fusion temperature before passingthrough the nip area. Preferably, the release coating on the raisedsurface roller comprises a polymer. Preferably, the release coating is apolyinfused coating. Preferably, the polyinfused coating comprisespolytetrafluoroethylene. Preferably, the edges of the raised surface ofthe raised surface roller have a radius of curvature of from 1/256 inchto ⅜ inch.

Preferably, the process further comprises cooling the first and secondfilms after heating the selected portions of the films, the coolingbeing carried out by a means for cooling. The means for cooling can be,for example, ambient air impingement, refrigerated air impingement,forwarding the film through ambient for a time period long enough toeffect cooling, contact with fluid (preferably water), radiativecooling, etc. Preferably, the means for cooling comprises bringing thefirst film or the second film into contact with a cooling roller.Preferably, the cooling roller has a Shore A hardness of from 40 to 100.Preferably, the cooling roller also has a release coating thereon, aswell as a composition which increases the rate of heat transfer throughthe release coating on the cooling roller.

In the process of the present invention, preferably both the first filmand the second film are provided from first and second rolls of film(i.e., rollstocks), respectively. Alternatively, a double-wide flat film(or a double-wide seamless film tubing) on a single roll can be unwoundand slit to provide both the first film and the second film. A flat filmcan be centerfolded, with one side (i.e., “leaf”) being the first film,and the other side being the second film, with the first and secondfilms being connected by the centerfold line before being brought intocontact with one another. The double-wide seamless film tubing, preparedby extrusion from an annular die, can likewise be slit open along oneedge, in order to provide the equivalent of the centerfolded filmdescribed above.

Alternatively, either the first film or the second film can be supplieddirectly from an extrusion process with the other film being providedfrom a rollstock. It is preferred that any film(s) provided fromrollstock are stress relaxed by a means for stress relaxation, i.e., ameans for annealing. Preferably, the means for stress relaxation isperformed immediately upon unwinding the film from the rollstock butbefore contacting the first and second films together. Preferably, themeans for stress relaxation heats the part of all of the film to atemperature above a Vicat softening point of but below a glasstransition temperature, so that the film is de-stressed. Stress reliefprovides the film(s) with enhanced flatness so that the film liessmoothly on the raised surface roller, and so that the films are flatrelative to one another in order to improve the uniformity of thedesired film-to-film contact during downstream processing.

In one embodiment, the contacting of the first film with the second filmis carried out before heating either film, i.e., while forwarding thefirst film and second film together at the same speed, upstream of theraised surface roller. In another embodiment, a selected portion(s) ofthe first film is heated before the first and second films come intocontact with one another. This can be done by having the first filmcontact the raised surface roller before the first film contacts thesecond film, so that film-to-film contact and heat sealing are nearlysimultaneous. During heat sealing, preferably heat and pressure areapplied simultaneously.

Heating sealing is preferably performed by passing the first and secondfilms together through a nip between a first roll (herein referred to asthe “raised surface roller”) and a second roll (herein referred to a the“contact roller”), with at least one of the rolls having a patternedraised surface and at least one of the pair of rolls being heated. Theraised surface roller has the patterned raised surface. Preferably theraised surface roller is heated and the contact roller is not heated.Alternatively, if both the first roll as well as the second roll can beprovided with a raised surface (and alternatively, both can also beheated), in which case the raised surfaces of the first and second rollsare operatively aligned, so that together they can effect a heat-sealingof the selected portion of the first film to the selected portion of thesecond film. Preferably, each roll with a raised surface has acontinuous raised surface so that the nip between the first and secondrolls is maintained throughout rotation of the first and second rolls,without further means to maintain the nip. A continuous nip ensurescontinuous forwarding of the first and second films. If a roll does nothave a raised surface, preferably such roll has a smooth continuoussurface to ensure that the nip is maintained throughout rotation of theroll. Alternatively, means can be provided to maintain the nip betweenirregular rolls and between rolls having discontinuous raised surfaces,such as overlapping raised surfaces, and/or a resilient surface on oneor more of the rolls, and/or a roll on a moveable axis with forcecontinuously urging the rolls into contact with one another despiteirregularities. Preferably, the first and second films are heat sealedto one another in a repeating pattern which results in one or moresealed areas in combination with one or more unsealed areas.

BRIEF DESCRIPTION OF THE DRAWINGS

The numerous features and advantages of the present invention are betterunderstood by those skilled in the art by reference to the accompanyingdetailed description and the following drawings, in which:

FIG. 1 is a schematic of a preferred process for making the inflatablearticle.

FIG. 2 is a schematic of a first alternative process for making alaminated article.

FIG. 3 is a more detailed diagrammatic view of a section of aninflatable article.

DETAILED DESCRIPTION OF THE INVENTION

In the process of the present invention, an inflatable article is madefrom either two discrete films, a tubular film which is slit, or afolded flat film. The films are sealed to one another in selected sealregions, forming a pattern of sealed and unsealed areas, the latter ofwhich define chambers, inflation channels, connecting passageways, aninflation skirt, and optionally one or more inflation manifolds that canbe inflated, thereby ultimately (i.e., upon inflation and sealing toentrap the inflation gas or fluid) providing cushioning pockets orbubbles within the laminate. The invention is used to fabricate laminatematerials from polymeric resins in a one stage process that eliminatesdisadvantages associated with multiple stage processes.

In the FIG. 1 process schematic, roll 6 of first film 8 is unwound withfirst film 8 being directed onto and passing partially around thesurface of hot raised surface roller 16, before first film 8 contactssecond film 10 which is provided from roll 12. First film 8 is heated byhot raised surface roller 16. When first film 8 and second film 10 passthrough nip 17 between raised surface roller 16 and contact roller 15,the heat and pressure to which films 8 and 10 are subjected forms a heatseal between first film 8 and second film 10. Thereafter, films 8 and 10pass further around raised surface roller 16, and through nip 19 betweenraised surface roller 16 and cooling roller 18. Thereafter, films 8 and10 make a partial wrap around cooling roller 18, and emerge therefrom asinflatable laminate web 20.

The raised surface of raised surface roller 16 heats that portion offilm 8 which contacts the raised surface of roller 16. Heat istransferred from the raised surface of roller 16, through a heatedportion of film 8, eventually heating through to a corresponding portionof film 10 to be heat sealed to film 8. Upon passing about 180 degreesaround raised surface roller 16, heated films 8 and 10 together passthrough second nip 19, which subjects heated films 8 and 10 to about thesame pressure as is exerted in first nip 17, resulting in a patternedheat seal between films 8 and 10. Preferably, nips 17 and 19 eachsubject films 8 and 10 to a pressure of from 2 to 10 pounds per linearinch, more preferably 2 to 6 pounds per linear inch, more preferablyabout 4 pounds per linear inch.

Raised surface roller 16 comprises raised surfaces 24, recesses 25, andrecessed surfaces 26. Raised surface roller 16 is a heat transferroller. Raised surface roller 16 preferably has a diameter of 12 inchesand is preferably heated by circulating hot oil therethrough so that thesurface is maintained at a temperature of from 280° F. to 350° F., withthe edges of its raised surfaces being rounded over to a radius of 1/64inch.

In order to carry out the process at relatively high speed, e.g., aspeed of at least 120 feet per minute, preferably from 150 to 300 feetper minute, but up to as high as 500 feet per minute, it has been foundto be important to provide the manufacturing apparatus with severalfeatures. First, the raised surface roller should be provided with arelease coating or layer. The release coating reduces adherence withfilm 12 while film 12 contacts raised surface roller 16, andparticularly when film 12 releases from roller 16. At least a portion ofrelease coating 28 is infused with one or more polymers. The polymerinfused can be any conventional polymer used for reducing adherence topolymer films, for example, Teflon® polytetrafluoroethylene. Raisedsurface roller 16 can be infused by any conventional infusion process.As used herein, the phrase “release coating” is inclusive of all releasecoatings and layers, including polyinfused coatings, applied coatingssuch as brushed and sprayed coatings which cure on the roll, and even arelease tape adhered to the roll.

A preferred release coating composition comprise Teflon®polytetrafluoroethylene. More particularly, raised surface roller 16 hasan infused Teflon® polytetrafluoroethylene coating thereon (i.e., apolyinfused coating, which was a SF-2R coating {less preferably, an SFXcoating}) prepared by General Magnaplate, at 1331 US1, Linden, N.J.,07036, with the raised surface(s) being above the background by adistance of ¼ inch (0.64 cm).

Preferably, the raised surface of roller 16 is also textured to reduceadherence to polymer films. More particularly, the raised surface ofraised surface roller 16 is provided with a surface roughness of from 50to 500 root mean square (i.e., “rms”), preferably 100 to 300 rms, morepreferably about 250 rms. This degree of roughness improves the releasequalities of raised surface roller 16, enabling faster process speedsand a high quality product which is undamaged by licking back on roll16.

Films 8 and 10 preferably contact raised surface roller 16 for adistance of about 180 degrees. The edges of the raised surfaces shouldbe rounded off to a radius large enough that the film readily releaseswithout snagging on an edge due to its “sharpness” relative to thesoftened film, and to prevent damage to the hot films during passagethrough a nip between the raised surface roller and the contact rollerand especially when passing through a nip between the raised surfaceroller and the cooling roller. Preferably, the radius of curvature onthe edges of the raised surface is from 1/256 inch to ⅜ inch, morepreferably from 1/128 inch to 1/16 inch, more preferably from 1/100 inchto 1/32 inch, and more preferably about 1/64 inch, i.e., about 0.04 cm.

Contact roller 15 applies pressure to films 8 and 10 as they passthrough nip 17. The present invention is not limited to contact roller15, but rather encompasses other contact surfaces formed on otherapparatus, such as a planer surfaces, curved surfaces, or portion of aclamp, as will be understood by persons familiar with film processingtechnology in view of the present disclosure. Preferably, contact roller15 has an elastic outer coating 13 comprising rubber. Preferably,elastic outer coating 13 provides roller 15 has a Shore A hardness offrom 50 to 110, more preferably from 55 to 85, more preferably from 60to 80, more preferably about 70. Alternatively, contact roller 15 has arelease coating thereon, which preferably comprisespolytetrafluoroethylene.

Contact roller 15 applies pressure to films 8 and 10 as they passthrough nip 17. The present invention is not limited to contact roller15 but rather encompasses other contact surfaces formed on otherapparatus, such as a planer surfaces, curved surfaces, or portion of aclamp, as will be understood by persons familiar with film processingtechnology in view of the present disclosure.

It is also important to provide the cooling roller downstream of and innip relationship with the raised surface roller, with a release coatingor layer, as described above. Preferably, the cooling roller ismaintained at a temperature below the fusing temperatures of films,using conventional cooling techniques. The cooling roller solidifies theheated portions of the first and second films. The present invention isnot limited to one cooling roller 18, but rather further encompasses theuse of two or more cooling rollers in the process, i.e., downstream ofthe heated raised surface roller 16. Moreover, any suitable means forcooling could be used in place of one or more cooling rollers, such ascooled planer surfaces, cooled curved surfaces, cooled clamping surfacesof any shape, cool fluids and gases, etc., as will be understood bypersons of skill in the art of film manufacture and processing.

The cooling roller lowers the temperature of the selected heatedportions of the laminate, in order to cool the heat seals so that theybecome strong enough to undergo further processing without being damagedor weakened. Moreover, the means for cooling is preferably immediatelydownstream of the heating means (i.e., the raised surface roller), inorder to reduce heat seepage from the still-hot seals to unheatedportions of film, to prevent unheated portions of laminated article frombecoming hot enough to fuse the films in an area intended to serve as aninflation chamber or inflation passageway.

Preferably, films 8 and 10 make a partial wrap of about 90 degreesaround heat transfer roller 18 (i.e., a cooling roller), which has adiameter of 12 inches and which has cooling water passing therethrough,the cooling water having a temperature of from 100° F. to 150° F.Preferably, cooling roller 18 has a ¼ inch thick (about 0.64 cm thick)release and heat-transfer coating thereon (not illustrated). The coatingis made from a composition designated as “Thermosil® 70 Brown”, whichwas provided and applied to a metal roller by United Silicone ofLancaster, N.Y. The coating contained silicone rubber to provide coolingroller 74 with a Shore A hardness of from 50 to 110, preferably 55-85,more preferably 60-80, and still more preferably about 70. TheThermosil® 70 Brown composition also contained one or more fillers toincrease the heat conductivity to improve the ability of cooling roller18 to cool the still hot films, now sealed together to result ininflatable article 20, which was thereafter rolled up to form a roll forshipment and subsequent inflation and seating, to result in a cushioningarticle.

Although cooling step 6 can be passive (e.g., in that the heat seals aresimply allowed to cool by giving off heat to the ambient environment),it is preferably active in order to quickly cool the heat sealsimmediately after formation, so that the heat seal is not damaged orweakened by continued processing. Preferred cooling means are asdescribed above.

The process can be further assisted by an apparatus capable of adjustingthe temperature of films to maximize film fabrication speeds.Optionally, one or more transfer rollers (not illustrated) can be usedbetween roll 6 and raised surface roller 16, as well as between roll 12and raised surface roller 16. The transfer rolls can be at ambienttemperature or optionally can be heated or cooled in order to preheat orcool the film(s) before contact with raised surface roll 16 or oneanother. Preheating of film from a rollstock can assist in fast heatsealing. Cooling of a films provided via extrusion (vs. rollstock) canassist in downstream processing by quickly bringing the film down to (orbelow) a temperature suitable for passage through nip 17 and formationof the heat seal.

The present invention is inclusive of the heat-sealing of two monolayerfilms to one another, heat sealing a multilayer film to a monolayerfilm, and heat sealing two multilayer films to one another.

FIG. 2 is a diagrammatic view of another alternative process 14 formaking an inflatable article. In FIG. 2, first and second films 8 and 10are in mutual contact when first film 8 contacts raised surface roller16 before films 8 and 10 enter nip 17. First film 8 and second film 10are heated by raised surface roller 16 as they are advanced through nip17 between raised surface roller 16 and contact roller 15.

The methods and apparatus of the present invention can be operated at ahigher output than conventional processes, including for example filmoutputs of more than 250 feet in length of film per minute. In addition,the methods produce larger width films than conventional processes,including for example, widths greater than 36 inches. The increase infilm width and in rate of film produced thereby permits an increase inthe surface area of laminated material produced more efficiently and atlower cost compared to conventional methods.

The methods of the present invention have an advantage over conventionalmethods of making protective laminates and bubble film because thepresent methods do not require thermoforming of the structure of thelaminate material during the heat sealing process by vacuum stretchingthe films. However, the present invention is not limited to methods thatdo not distort and/or deform the films, but rather encompassesconventional vacuum stretching techniques as will be understood bypersons familiar with film processing technology in view of the presentdisclosure.

Raised surfaces 24 and recessed surfaces 26 form a patterned heat seal27 in laminate material 20 as explained more fully above with referenceto FIG. 1 and FIG. 2. Raised surfaces 24 extend away (i.e., outward)from recessed surfaces 26 thereby forming a pattern for the heat seal(s)to be made to form the inflatable article. Recess surfaces 26 are not incontact with contact surface 16 while raised surface roller 16 is incontact with roller 15.

In an alternative embodiment of the present invention (not illustrated),contact roller 15 has raised surfaces that correspond to raised surfaces24. Contact roller 15 has recesses and recessed surfaces that correspondwith recesses 25 and recessed surfaces 26.

The term “nip” as used herein refers to a contact area between tworollers. First film 8 and second film 10 are in contact as they passthough nip 17. As first and second films 8 and 12 pass through nip 17,heat and/or pressure are applied to selected portions of first andsecond films 8 and 10, fusing the films together to form patterned heatseals schematically illustrated as 27 in FIG. 3.

First and second films 8 and 10 can be monolayer films, or multilayerfilms. If multilayer, they can be coextruded through annular or slotdies, extrusion coated, and can be produced by cast or blown filmprocesses. In one embodiment, first and second films 8 and 10 aretoughened by crosslinking via chemical cross-linking or irradiationtechniques known to those of skill in the art.

The process and apparatus illustrated in FIG. 1 can also be supplementedwith additional optional components and steps. More particularly, one orboth of films 8 and 10 can be preheated to a temperature below theirfusing temperature, so that less heat need be added by raised surfaceroller 16. In this manner, the process can be operated at higher speed,and/or the heat seal may be made stronger or of otherwise higherquality. Preheating can be carried out by, for example, providingadditional heated rolls for each of films 8 and 10, in advance of heatedraised surface roller 16. Optionally, additional nip means (i.e.,rollers or otherwise) can be provided against raised surface roller 70,to provide additional pressure points for the formation of strong heatseals at high manufacturing speeds.

FIG. 3 is a schematic view of laminate material 20. In FIG. 3, laminatematerial 20 comprises first film 8 heat sealed to second film 10 in aparticular heat seal pattern. Laminate 20 has heat sealed portion 40, aswell as unsealed portion 41. Heat sealed portion 40 is continuous alongthe machine direction of inflatable laminate article 20, with sealedportion 40 corresponding to a preferred raised surface pattern forraised surface roller 16 of FIG. 1. Unsealed portion 41 is alsocontinuous along the machine direction of article 20, with unsealedportion 41 corresponding to a preferred recessed surface pattern (i.e.,background pattern) of raised surface roller 16 and 70. Unsealed portion41 is arranged to form a pattern that includes distinct air chambers,connecting channels, as well as leaving a skirt (i.e., film flaps) foruse in inflating the inflatable article. Optionally, the unsealedportion could further include a passageway in the machine directionwhich serves as a manifold, i.e. connecting each of the passagewaysalong an edge of the article. However, a skirt is preferred. Preferably,the inflatable chambers have an uninflated diameter of about 1.75inches, and the passageways connecting the inflatable chambers have anuninflated width of ⅜ inch, and the seals are made so that the edges ofthe inflatable chambers and passageways are free of inflection pointswhich can produce unwanted stresses during inflation and use of theproduct.

The films referred to herein preferably comprise a polyolefin, such asfor example a low density polyethylene, a homogeneousethylene/alpha-olefin copolymer (preferably a metallocene-catalyzedethylene/alpha-olefin copolymer), a medium density polyethylene, a highdensity polyethylene, a polyethylene terapthalate, polypropylene, nylon,polyvinylidene chloride (especially methyl acrylate and vinyl chloridecopolymers of vinylidene chloride), polyvinyl alcohol, polyamide, orcombinations thereof.

Preferably, laminate materials 20 are as thin as possible, in order tominimize the amount of resin necessary to fabricate laminate materials20, but at the same time are thick enough to provide adequatedurability. Preferably, each of first and second films 8 and 10 have agauge thickness of from about 0.1 to about 20 mils. More preferably,each film layer has a total gauge thickness from about 0.5 to about 10mils, more preferably from about 0.8 to about 4 mils, and even morepreferably from about 1.0 to about 3 mils.

If desired or necessary, various additives are also included with thefilms. For example, additives comprise pigments, colorants, fillers,antioxidants, flame retardants, anti-bacterial agents, anti-staticagents, stabilizers, fragrances, odor masking agents, anti-blockingagents, slip agents, and the like. Thus, the present inventionencompasses employing suitable film constituents.

Preferably first and second films 8 and 10 are hot blown films having anA/B/C/B/A structure which has a total thickness of 1.5 mils. The Alayers together make up 86 percent of the total thickness, each of the Blayers making up 2% of the total thickness, and the C layer making up10% of the total thickness. The C layer is an O₂-barrier layer of 100%Caplon® B100WP polyamide 6 having a viscosity of Fav=100, obtained fromAllied Chemical. Each of the B layers are tie layers made of 100%Plexar® PX165 anhydride modified ethylene copolymer from QunatumChemical. Each of the A layers are a blend of 45% by weight HCX002linear low density polyethylene having a density of 0.941 g/cc and amelt index of 4, obtained from Mobil, 45% by weight LF10218 low densitypolyethylene having a density of 0.918 g/cc and a melt index of 2,obtained from Nova, and 10% by weight SLX9103 metallocene-catalyzedethylene/alpha-olefin copolymer, obtained from Exxon.

The laminates formed according to the present invention will resistpopping when pressure is applied to a localized area because channels ofair between chambers provide a cushioning effect. The laminates alsoshow excellent creep resistance and cushioning properties due tointer-passage of air between bubbles.

The various terms and phrases utilized throughout this document are tobe given their ordinary meaning as understood by those of skill in theart, except and to the extent that any term or phrase used herein isreferred to and/or elaborated upon in U.S. Pat. No. 5,837,335, toBabrowicz, entitled High Shrink Multilayer Film which Maintains Opticsupon Shrinking, issued Nov. 17, 1998, which is hereby incorporated inits entirety by reference thereto, and which supplements the ordinarymeaning of all terms, phrases, and other descriptions set forth herein.

In the figures and specification, there have been disclosed preferredembodiments of the invention. All sub-ranges of all ranges disclosed areincluded in the invention and are hereby expressly disclosed. Whilespecific terms are employed, they are used in a generic and descriptivesense only, and not for the purpose of limiting the scope of theinvention being set forth in the following claims.

Those skilled in the art will appreciate that numerous changes andmodifications may be made to the embodiments described herein, and thatsuch changes and modifications may be made without departing from thespirit of the invention.

1. A process for making an inflatable laminated article, comprising thesteps of: (A) contacting a first film with a second film; (B) heatingselected portions of at least one the first and second films to atemperature above a fusion temperature of the first and second films, sothat the first and second films are heat sealed to one another toproduce a laminated article having heat seal pattern which provides aplurality of inflatable chambers between the first film and the secondfilm; wherein the first and second films are forwarded at a speed of atleast 120 feet per minute while coming into contact with one another,and wherein the heating is carried out by contacting the first film witha heated raised surface roller having a release coating thereon.
 2. Theprocess according to claim 1, wherein the raised surface roller has asurface roughness of from 50 to 500 rms.
 3. The process according toclaim 1, wherein the first and second films are heat sealed to oneanother under a combination of heat and pressure.
 4. The processaccording to claim 3, wherein the pressure is produced by means forforming a nip area.
 5. The process according to claim 4, wherein thefirst film is brought into contact with the raised surface roller andheated to the fusion temperature before passing through the nip area. 6.The process according to claim 4, wherein the means for forming a niparea is a contact roller in a nip relationship with the raised surfaceroller.
 7. The process according to claim 6, wherein the contact rollerhas an elastic outer coating comprising rubber.
 8. The process accordingto claim 1, wherein the release coating on the raised surface rollercomprises a polymer.
 9. The process according to claim 8, wherein therelease coating is a polyinfused coating.
 10. The process according toclaim 9, wherein the polyinfused coating comprisespolytetrafluoroethylene.
 11. The process according to claim 1, hereinthe raised surface roller has edges of raised surfaces having a radiusof curvature of from 1/256 inch to ⅜ inch.
 12. The process according toclaim 1, further comprising cooling the first and second films afterheating the selected portions of the films, the cooling being carriedout by a means for cooling.
 13. The process according to claim 12,wherein the means for cooling comprises bringing the first film or thesecond film into contact with a cooling roller.
 14. The processaccording to claim 12, wherein the cooling roller has a Shore A hardnessof from 40 to
 100. 15. The process according to claim 13, wherein thecooling roller has a release coating thereon.
 16. The process accordingto claim 15, wherein the release coating on the cooling roller comprisespolytetrafluoroethylene.
 17. The process according to claim 1, whereinat least one member selected from the first film and the second film isprovided from a rollstock.
 18. The process according to claim 17,wherein any film provided from a rollstock is stress relaxed by beingheated to a temperature above a Vicat softening point of but below aglass transition temperature before being brought into contact withanother film.
 19. The process according to claim 17, wherein the firstfilm is provided from a first rollstock and the second film is providedfrom a second rollstock.